Destroy window before cleaning up combobox

fpdfsdk/formfiller/cffl_formfiller.cpp

 // Copyright 2014 PDFium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
 
 #include "fpdfsdk/formfiller/cffl_formfiller.h"
 
 #include "core/fpdfapi/fpdf_page/include/cpdf_page.h"
 #include "core/fxge/include/cfx_renderdevice.h"
 #include "fpdfsdk/include/cpdfsdk_widget.h"
 #include "fpdfsdk/formfiller/cba_fontmap.h"
 #include "fpdfsdk/include/fsdk_common.h"
 #include "fpdfsdk/include/fsdk_mgr.h"
 #include "fpdfsdk/pdfwindow/PWL_Utils.h"
 
 #define GetRed(rgb) ((uint8_t)(rgb))
 #define GetGreen(rgb) ((uint8_t)(((uint16_t)(rgb)) >> 8))
 #define GetBlue(rgb) ((uint8_t)((rgb) >> 16))
 
 #define FFL_HINT_ELAPSE 800
 
 CFFL_FormFiller::CFFL_FormFiller(CPDFDoc_Environment* pApp,
                                  CPDFSDK_Annot* pAnnot)
     : m_pApp(pApp), m_pAnnot(pAnnot), m_bValid(FALSE), m_ptOldPos(0, 0) {
   m_pWidget = (CPDFSDK_Widget*)pAnnot;
 }
 
 CFFL_FormFiller::~CFFL_FormFiller() {
+  DestroyWindows();
+}
+
+void CFFL_FormFiller::DestroyWindows() {
   for (const auto& it : m_Maps) {
     CPWL_Wnd* pWnd = it.second;
     CFFL_PrivateData* pData = (CFFL_PrivateData*)pWnd->GetAttachedData();
     pWnd->InvalidateProvider(this);
     pWnd->Destroy();
     delete pWnd;
     delete pData;
   }
   m_Maps.clear();
 }
@@ skipping 675 matching lines @@
   }
 }
 
 void CFFL_Button::OnDrawDeactive(CPDFSDK_PageView* pPageView,
                                  CPDFSDK_Annot* pAnnot,
                                  CFX_RenderDevice* pDevice,
                                  CFX_Matrix* pUser2Device,
                                  uint32_t dwFlags) {
   OnDraw(pPageView, pAnnot, pDevice, pUser2Device, dwFlags);
 }